Z. 


wl 


J 


4 


live 














Publication No. DP-108 


Copyright 1920 by Duplex Lighting Works 
Manufactured by 


DUPLEX LI GHTl NG WORKS 


OF GENERAL \ Wy, ELECTRIC CO. 
)U PLEX" (LIGHTING F 
eS Necessary T= Rerinement & 
Tips 


6 WEST 48 th. STREET 
NEW YORK CITY 






Duplexalites are sold by Electrical Dealers and Contractors 


WITHOUT 
DUPLEXAL 





Examples of Good and Bad Lighting Using the 
Same Lamp and Shade 


Two 


ido el omoOO Mn GETING? 





Brome hte sound orethe Shady 
Side of a Tree on a Sunny Afternoon 


ET US substitute for the sun a MAZDA C 
lamp, for the sky the ceiling of your room, 
and for the tree the Duplexalite. From the 

ceiling you now get a soft radiance which floods the 
entire room as completely as though it were open 
to the sky. From the diffusing disc of the Duplex- 
alite, you get a generous addition of light directly 
beneath, which has all the directional qua.ity of 
sunlight filtered through foliage. At the same 
time, the Duplexalite is protecting your eyes from 
the brilliancy of the MAZDA C lamp as comfortably 
as the tree offers protection from the glare of the 
sun. 


You can no more dispense with the ceiling re- 
flection than you can the sky. Nor would the 
unshaded brightness of the MAZDA C lamp offer 
any more advantage to see by than the desert sun 
at noon. 


By means of Duplexalite, the MAZDA C lamp 
has been equipped in a way to produce the most 
charming lighting effect that occurs in nature. 


Good lighting is the proper distribution of light. 


Three 


THE MAZDA C LAMP 


The MAZDA C Lamp is the 
Sun of Artificial Lighting 


E all know what happened to 

the man who took a long look 
into the face of the noon-day sun’ 
before smoked glasses wereinvented. 
Of course it was unnecessary. It is 
equally unnecessary to gaze directly 
at the filament of the MAZDA C 
lamp. 

The MAZDA C lamp surpasses all 
others in efficiency, both when new and 
throughout the useful life of each lamp. 
After much study and experiment, devices have 
been designed to control this wonderful brightness 
and distribute it wisely for the benefit of eyes and 
nerves, to our great comfort and efficiency. To use 
such devices is not only desirable, but necessary. 
When this is done the MAZDA C lamp provides 
the best lighting obtainable and at the least expense. 





The highest efficiency lamps that are made in small sizes are 


the MAZDA B lamps. The following diagram illustrates 
the economy of using a MAZDA C lamp instead of 
several smaller lamps 


baa - 9 - 


THREE 60-WATT MAZDA B LAMPS USE 180 WATTS AND GIVE 17262 LUMENS (UNITS OF LIGHT) 


Val 
her dy 
fe ~~ 4 
WwW IN f 
oF ‘ 
} 
wae 

ONE 160-WATT MAZDA C LAMP USES 150 WATTS AND GIVES 2049 LUMENS ‘UNITS OF LIGHT) 















WV elon ls) a el eC eC INCs 


The Duplexalite Shades the MAZDA C 
Lamp and Diffuses its Brightness 


[DUPLEX Lighting is the natural method of light 
distribution because it combines a day-like dif- 
fusion with direct lighting where most needed. 

In every other method of illumination, the element 
of direct lighting is either lacking or is radiated at 
unnatural angles at which the eye has no protection. 
The result is the sensation commonly complained of 
as “‘glare.”’ 

In a Duplexalite, more than 96% of the light 
given off is deflected in useful directions; that is, 
upward for ceiling reflection and downward for ad- 
ditional intensities—Duplex Lighting. Less than 
4% of the light is given off at angles which produce 
glare, as compared with the usual 30% to 45% with 
other systems in which any appreciable amount of 
direct lighting is provided. 


The diagram below indicates the principles of Duplex Light- 
ing and the typical design of the Duplexalite 




































































Five 


The Standard Duplexalite 





STANDARD DUPLEXALITES 


THE Standard Duplexalite is the basis of all forms 

of Duplexalites. It consists of the ceiling plate 
or canopy adapted to all standard ceiling outlets, a 
suspension made of specially constructed silk-covered 
cable with strain-relief grips at top and bottom, 
lamp socket, a characteristic metal deflector and 
moulded glass disc, all in the correctly focused 
position for the rated sizeof MAZDA Clamp. The 
deflector, socket-cover and canopy are finished in 
a matt-surfaced ivory porcelain enamel. The in- 
terior reflecting surface is of polished white enamel. 
Wattage of 
















Length Diameter of 

























Number Lamp Socket Over All Deflector 
D-131 100-150 Medium 36/” 12/0 
200 Medium 48” 14” 
300-500 Mogul 60/" 16” 









The Duplexalite is adapted to any requirement where gocd lighting is 
sought. In the home it can he used in every room—kitchen, dining room, 
living room, library, nursery, bedrooms, bathrooms, etc. Below is a 
picture of the kitchen of the Good Housekeeping Institute. The Duplex- 
alite was tested by their department of Household Engineering and was 
awarded the official approval of the Institute, Serial Number 2009. 


proeiidiati 





oe. eee eee ema 
Good Housekeeping Institute Kitchen 


Seven 


DECORATIVE POSSIBIUI Ti Bs Gr 
DUPER XS IGE ING 


The Unseen Duplexalite Enhances a Beautiful 
Shade and Produces a Beautiful Lighting Effect 


HE characteristic distribution of light from the 

Duplexalite opens up an entirely new field of 
decorative possibilities. 

The self-illumination of the Duplexalite reflector 
is sufficient to attractively illuminate any form of 
decorative shade without interfering in any way 
with the upward and downward lighting. Duplex- 
alite shades are illuminated for the purpose of 
beautifying them, instead of being over-lighted for 
the purpose of general illumination. This permits 
of the use of almost any translucent fabric which 
may happen to meet a decorative requirement or 
suit an individual taste. The illumination produced 
a » with a Duplexalite 
is unchanged by 
the addition of the 
shade. 








Examples of Duplex Lighting with and without a shade 





Eight 


PHANTOM VIEW OF EMPIRE 
DURE ESSAI TE 





es this illustration a Duplexalite shade (of silk) and the 
Duplexalite deflector (of metal) are shown as transparent 
in order to illustrate clearly the mechanical construction of 


this effective lighting device, 


All light from the brilliant fila- 
ment of the MAZDA C lamp is 
utilized in the following way: 


1—From the top of the deflector 
a large portion of the rays go 
directly from the lamp to the 
ceiling. 


2—All rays intercepted by the metal 
deflector, which is white enam- 
eled inside, are deflected either 
upward to the ceiling or down- 
ward through the diffusing disc. 


3—The rest of the light rays go 
directly from the lamp to the 
glass diffusing disc, through 
which the direct light is filtered 
to an agreeable softness. 


4—A small amount of the light is 
reflected upward from the outer 
edge of the diffusing disc so that 
it illuminates the outside of the 
metal deflector. It is this which 
provides the soft beautifying 
illumination of the Duplexalite 
shade, 





In addition to the lighting ad- 
vantages, please note also the fol- 
lowing practical conveniences: 


1—The Duplexalite shades may be 
removed by tilting and taking 
off sideways. They may be put 
away for the summer with the 
curtains, changed from warm 
colored silks in winter to bright 
figured cretonnes in summer, or 
changed from room to room in 
a few moments for special occa- 
sions. 

2—Raising the metal deflector 
straight up a few inches unlocks 
the diffusing disc which may be 
washed as easily as a lunch 
plate, and may be locked into 
place again by merely raising 
and lowering the deflector. 

3—The deflector is finished in por- 
celain enamel and is easily kept 
clean by occasional dusting. 


4—Douplexalite construction affords 
the most perfect ventilation, 
thus insuring the longest life 
and efficiency of the MAZDA C 
lamp, - 


Nine 





Shade No. 5021 
ON STANDARD DUPLEXALITE 


Ten 


Poe ie OUP EOxX AISLES 


ie Empire Shade is historic. In its dignified simplicity, 
it embodies the typical construction of all Duplexalite 
shades, consisting of an upper ring with projecting supports 
which rest on the deflector, and a substantial frame over 
which the shade is formed. Its conventional lines conform 
to the best standards of taste for a wide variety of uses. 
Empire Shades are made of silk gathered on the frame with 
silk lining and gimp trimmings. 


TheEmpire 
shade may be 
ornamented 
Wet Canwotet. 
changing the 
appearance cf 
dignity and 
simplicity. 

Em pire 
shadesare 
made in old 
rose, old gold, 
ecru or blue. 





Shade No. 5037 





Reception Hall of a New York Residence which is lighted 
throughout with Duplexalite 


Eleven 


i tatoos 
PRN 924 


~—s 
Lccudiabae 


Shade No. 5020 and Tassel ‘*D”’ 


ON STANDARD DUPLEXALITE 


Twelve 





Pee ele ele iP LR 
DUPLEXALEPES 


TE decorative Empire shades are made of colored 
silks covered with figured net and trimmed with gold 
or colored braids to harmonize with the colored pattern. 
The delicate traceries are thrown into just the right relief on 
a Duplexalite. The patterns are consequently very effective, 
whether seen lighted or by daylight. 


Figured Net Shades are made in the following colors: 


Color “A*’—Blue and gold figured net over gold silk lining, 
trimmed with gold braid. 

Color "*B**—Net with ecru woven ground. Flowers in blue and 
mulberry. Gray silk lining. ‘Trimmed with blue 


braid. 
Color ""C*—Net with ecru woven ground. Flowers in old rose 
and blue. Old rose silk lining. Trimmed with old 


rose braid. 


TASSEL ‘“D"’—which is shown, covers the ivory socket cover 
and matches the old gold silk of the pendant. It is 
made of heavy silk fringe and can be put on at any time 
after the Duplexalite is installed. It is put on and 
taken off as easily and quickly as the Duplexalite shades. 





on ee Nik ae | 


Note how the Figured Net Shade Harmonizes with the 
Hangings in this Living Room 


Thirteen 


Shade No, 5010, Tassel ‘‘D’’ and Disc Screen ‘‘A’”’ 


ON STANDARD DUPLEXALITE 


Fourteen 





Die GeROOM DUPEEXALITES 
IDES Room Duplexalites are fitted with shades having 


the silk closely pleated and finished in ruching form at 
top and bottom. The silk lining is in every case of a warm 
colored tint. The Disc Screen is made of light silk trimmed 
with old gold braid, and covers the glass diffusing disc. 


Shade No. 5025 has double 
box pleated ruching at top and 
bottom and a heavy silk fringe. 

Dining Room Shades are 
made in ecru, old gold, old rose, 
delft blue, French gray or deep 
red. Disc Screens are made in 
old gold, old rose or ecru. 





Shade No. 5025 





S i 


The table lighting filters through a gold colored silken disc 
cover while the furniture in the background is enriched 
by the general illumination 


Fifteen 





Painted Parchment Shade No. 5012 and Tassel ““D” 


ON STANDARD DUPLEXALITE 


Sirteen 


PAINTED PARCHMENT DUPLEXALITES 


UPLEXALITE Parchment Shades are made in the 
Empire form and bound with antique gold galloon. 
They are among the most finished productions obtainable in 
decorative shades. 
Shade 
No. 5059 


Natural parch- 
ment, stripe top 
and bottom. (Blue 
unless otherwise 
specified). 
Shade 
No. 5051 

Hand painted. Birds 
of Paradise and foli- 


age on an antique 
background. 





PLAIN PARCHMENT DUPLEXALITES 


Silk tassel for 
socket cover is 
not included, 
and the effect 
obtained is one 
of extreme sim- 
plicity and high 
quality. 














Plain Parch- 
ment Shades 
have an antique 
finishandare 
bound with an- 
tique gold gal- 
loon. 


Painted Parchment Duplexalites ina Bachelor’s Drawing Room 


Seventeen 


Shade No. 5015 and Tassel ‘‘D”’ 
ON STANDARD DUPLEXALITE 


ighteen 





Hela Goals) Che Le exe Ts eS 


THE most natural form of Duplexalite Shade is 

that made of suitable materials suspended from 
a supporting ring. Somewhat less formal than 
Empire Duplexalites, the Ring Duplexalites offer an 
opportunity for a more intimate style of decoration. 

Figured Silk Ring Shades, as illustrated on the 
opposite page, are finished with antique gold braid 
and ornamental antique gold fringe. Mulberry, 
blue or gold ground. Shade No. 5019, below, is of 
draped China silk in solid colors; old rose, old gold, 
ecru or blue. Silk braid edging at top and uncut 
silk fringe at bottom, weighted. 





oa 


Shade 5022 


Cretonne shades are favored for Bedrooms; also for 
generalsummeruse. No.5018isanattractivenursery 
pattern. No. 5022 is furnished with either reds or 
yellow predominating, as ordered. 


Nineteen 


NO. 5605 





DUPLEXALITES WITH SPECIAL SHADES 


Shade No. 5005 The Duplexalite Hanger 
is of draped silk, lined. shown has a rigid stem wound with rich 
Trimmed with antique silk cord. It is furnished with a special 
gold lace and bullion tassel of silk and bullion fringe, and a 
fringe. Made in colors special ceiling canopy finished in gold or 
as ordered. silver, as ordered. 


Twenty 


DUPLEXALITES WITH SPECIAL SHADES 
Shade No. 5004-A Shade No. 5024 Shade No. 5004-B 


Black Japanese figures Octagonal shade, 
on ecru ground. shirred silk with fringe dark background. 
and antique gold 
braid. Made in colors 
as ordered, 


Oriental pattern, on a 


Twenty-one 





Shade No. 5052 
Antique gold lace over 
silk. Bullion and silk 

fringe.* 

Shade No. 5026 


Heavy, old gold silk 
fringe. Gold braid. 


Twenty-two 


& 


SHA 


Shade No. 5040 


Gold metal lace over 
shirred _ silk. Gold 
braid and flowers.* 


*Made in colors as 
ordered. 





iat! 


DUPLEXALITES WITH SPECIAL S 


DE NO. 5035 





HADE 


Shade No. 5035 


Draped chiffon over 
silk; Galloon braid 
and flowers.* 


Shade No. 5002 


Stretched silk, gold 
and silk braid.* 





THE ETRUSCAN DUPLEXALITE 


Dull glazed porcelain enamel in shaded golden brown, decoration fused 
into the surface in darker tone. Designed for requirements where a 


neat, though rich, ornamental fixture is appropriate and no shade is 
desired, 


Twenty-three 





Duplexalite Diffusing Disc 








Disc Screen **B”’ 
Tassel ‘‘D’’ 


HE DIAGRAM below shows the proper hanging length 

to obtain most uniform light distribution. The shadow 
line (A) should meet the junction of ceiling and walls. For 
home lighting, evenness of illumination is not always neces- 
sary and the length may be increased, if desirable; although 
in most cases the hanging length, as sketched, will provide 
the most satisfactory appearance as well as the best lighting. 
The length is easily adjusted to suit the requirements when 
the Duplexalite is being installed. 


Hanging Length 





No. D-29 “‘Pullite’’ Canopy Switch should be specified where 
there is no wall switch. Ly 


Twenty-four 


DUPLEXALITES 


Wattage Length Diame- 

of Lamp Socket overall ter Price 
D-131 Standard Duplexalite 100-150 Medium 36” 12/* $16.00 
D-231 ii 200 Medium 48” 14” 19.00 
D-531 ae 300-500 Mogul 60’ 16” 24.00 
D-131 Etruscan Duplexalite 100-150 Medium 36’ QE 20.00 
D-231 SE = 200 Medium 48” 14” 25.00 
D-531 as 300-500 Mogul 60” 16” 30.00 
D-4131 Duplexalite Pg. 20 100-150 Medium 36” 12% 47.50 
D-4231 hs 200 Medium 48” 14” 52.50 
D-4531 oe 300-500 Mogul 60’ 16" 60.00 


Prices not including Mazda C Lamp. For Pullite Canopy 
Switch add $2.00. 


DUPLEXALITE SHADES 


100 Watt 200 Watt 500 Watt 
Shade Frame Shade Frame Shade Frame 
No. Complete Only Complete Only Complete Only 
S-5002 $24.00 $4.50 $26.00 $5.25 $30.00 $6.00 
S-5003 34.00 3.75 41.50 4.50 48.00 6.00 
S-5004 32.00 3.75 38.00 4.50 45.00 6.00 
S-5005 28.00 She 32.00 90 42.00 1.35 
S-5010 18.00 1.80 22.00 2.10 30.00 3.00 
S-5011 7.50 1.80 8.50 2.10 10.50 3.00 
S-5012 17.00 1.80 20.00 2.10 26.00 3.00 
S-5015 7.00 Pi 9.00 90 12.00 1.35 
S-5018 5.00 m3) 5.50 90 6.00 1.35 
S-5019 7.00 15 7.50 90 10.50 1.35 
S-5020 8.50 1.80 10.50 2.10 15.00 3.00 
S-5021 8.00 1.80 10.00 2.10 13.50 3.00 
S-5022 4.00 75 5.00 90 6.00 1.35 
S-5024 29.00 4.50 34.00 5.25 45.00 7.50 
S-5025 52.50 2.55 60.00 3.00 72.00 4.50 
S-5026 26.00 1.80 37.00 2.10 53.00 3.00 
S-5035 22.50 1.80 25.00 2.10 30.00 3.00 
S-5036 12.00 1.80 13.50 2.10 15.00 3.00 
S-5037 10.00 1.80 12.00 2.10 15.00 3.00 
S-5040 54.00 2.55 58.00 3.00 65.00 4.50 
S-5051 15.00 1.80 18.00 2.10 27.50 3.00 
S-5052 30.00 1.80 35.00 2.10 42.00 3.00 
S-5059 8.50 1.80 9.00 2.10 12.00 3.00 

ACCESSORIES ' 
100 Watt 200 Watt 500 Watt 
Frame Frame Frame 


Complete Only Complete Only Complete Only 
Disc Screen ‘‘A’’ $2.50 $ .60 $3.00 $ .75 $4.00 $ .90 
Disc Screen ‘‘B’’ 1.50 .60 2.00 .75 3.00 .90 
Stem Tassel ‘‘D’* 3.50 3.50 5.00 


On shades where color is optional we will match samples submitted 
as nearly as possible. On shades where definite colors are species 
an additional charge of 3314% will be made for delivery in colors 
not listed—and orders wil! be subject to delayed shipment. 


200 watt shades made to fit 100 watt Duplexalite—add 10%. 500 watt 
shades made to fit 200 watt Duplexalite—add 10%. 


Prices subject to change without notice 
DP-108A 9/20 


ae 


THE PHILADELPHIA ELECTRIC 


COMPANY SUPPLY DEPT. 
132 South Eleventh Street. 
Philadelphia 





